This application contains subject matter that is related to the subject matter of the following application, reference number 102192-US-00 (Ishiguro), which is assigned to the same assignee as this application and filed on the same day as this application. The below listed application is hereby incorporated herein by reference in its entirely: xe2x80x9cOptical Communication Modulexe2x80x9d by Yoshikawa et al.
1. Field of the Invention
This invention relates to an optical communication module.
2. Related Prior Art
An optical communication module includes an optical semiconductor device, a lead frame and a substrate disposing the semiconductor device and an optical fiber thereon. The optical coupling between the semiconductor device and the optical fiber is realized on the substrate and the substrate is secured on an island of the lead frame. Such optical module is disclosed in the U.S. Pat. No. 6,377,742.
In the conventional module shown in U.S. Pat. No. 6,377,742, however, it would be preferable for the manufacturing of the module that the level of the primary surface of the lead frame corresponds with that of the substrate.
The object of the present invention is to provide an optical communication module with a new configuration, in which the level of the lead frame and that of the substrate coincide to each other.
An optical module according to the present invention comprises a subassembly, a container, a lead frame fixed to the container, and a base member. The subassembly secures a semiconductor optical device and an optical fiber coupled to the semiconductor device. The base member supports the subassembly. The container comprises a pair of side portion extending along a first direction and a rear portion extending along a second direction intersecting the first direction. The device-mounted area is provided on the rear portion.
The lead frame is fixed to a first surface of the container, while the base member is fixed to a second surface opposing to the first surface. The pair of side portions of the container and the base member forms a room for securing the subassembly therein. According to the present configuration, the optical axis of the optical fiber enables to set substantially within the primary surface of the lead frame by adjusting the level of the base member. The container has a plurality of first regions on the first surface and second regions on the second surface. The lead frame is fixed to first regions, while the base member is attached to second regions.
The base member comprises a pair of frame portion, an island portion and a plurality of supporting portions. The frame portions extend along the first direction within a surface of the base member. The island portion is provided between the respective frame portions within the surface. The island portion holds the subassembly thereon. Respective supporting portions have at least a section, a thickness of which is thinner than the island portion. Thus, the supporting portion is easy to deform.
Further aspect of the invention is that the lead frame comprises a pair of fixing bar and a plurality of leads. Respective bars extend along the first direction and correspond to regions on the container, while a plurality of leads are along the second direction, hence tips of leads face to fixing bars.
The module is preferable to provide housing for covering the subassembly, the container and the lead frame. The housing may be made of a mold resin. The subassembly includes a ferrule for securing the fiber. The ferrule and leads protrude from the housing, on the other hand the subassembly, the container, and the base member is molded within the resin. The configuration of the present module is applicable to the resin-molded optical module.
The optical device is a light-emitting semiconductor device, such as laser diode or a light-receiving semiconductor device such as photo diode.